Photoconductive switch module

Abstract

The present invention is directed to a photoconductive switch module. The photoconductive switch module comprises a first substrate having light-emitting elements, and a second substrate having photoconductive switch elements, whose number is equal to that of the light-emitting elements. The light-emitting elements face the photoconductive switch elements, so that the photoconductive switch elements are turned on/off in accordance with lighting/extinction of the light-emitting elements. The photoconductive switch module further comprises a third substrate arranged between the first substrate and the second substrate. The third substrate has through holes, whose number is equal to that of the light-emitting elements. Each through hole is positioned between a light-emitting element and a photoconductive switch element facing each other. Drive light emitted from each light-emitting element travels to the photoconductive switch element via the through hole.

1. A photoconductive switch module comprising:
 a first substrate having light-emitting elements; 
 a second substrate having photoconductive switch elements, whose number is equal to that of the light-emitting elements, the light-emitting elements and the photoconductive switch elements being arranged to face each other, the photoconductive switch elements being turned on/off in accordance with lighting/extinction of the light-emitting elements; and 
 a third substrate arranged between the first substrate and the second substrate, the third substrate having through holes, whose number is equal to that of the light-emitting elements, each through hole being arranged between the light-emitting element and the photoconductive switch element facing each other, drive light emitted from each light-emitting element traveling to the photoconductive switch element via the through hole; 
 wherein the second substrate has a circuit wiring connected to the photoconductive switch elements on the side facing the third substrate, the third substrate has a concave portion extending along the circuit wiring, such that the through holes terminate on the bottom surface of the concave portion, and the third substrate has conductivity at least in the vicinity of the surface of the concave portion and the circuit wiring and the concave portion are arranged to face each other. 
 
   
   
     2. The photoconductive switch module according to  claim 1 , wherein the third substrate further has a convex portion protruding from the bottom surface of the concave portion, and the convex portion has a height equal to or smaller than a depth of the concave portion. 
   
   
     3. The photoconductive switch module according to  claim 2 , wherein the convex portion is positioned between the photoconductive switch elements to be reversely turned on/off. 
   
   
     4. The photoconductive switch module according to  claim 2 , wherein the convex portion and the second substrate are spaced with a gap equal to or smaller than 100 μm, and the convex portion has a thickness (dimension in a direction along which the concave portion extends) equal to or smaller than 100 μm. 
   
   
     5. The photoconductive switch module according to  claim 2 , wherein a height of the convex portion is equal to a depth of the concave portion. 
   
   
     6. The photoconductive switch module according to  claim 2 , wherein a height of the convex portion is smaller than a depth of the concave portion. 
   
   
     7. The photoconductive switch module according to  claim 2 , wherein the convex portion surrounds the through hole. 
   
   
     8. A photoconductive switch module comprising:
 a first substrate having light-emitting elements; 
 a second substrate having photoconductive switch elements, whose number is equal to that of the light-emitting elements, the light-emitting elements and the photoconductive switch elements being arranged to face each other, the photoconductive switch elements being turned on/off in accordance with lighting/extinction of the light-emitting elements; and 
 light isolation means for isolating the light between a pair of the light-emitting element and the photoconductive switch element from the light between another pair of the light-emitting element and the photoconductive switch element; 
 wherein the light isolation means comprises a third substrate arranged between the first substrate and the second substrate, the third substrate has through holes, whose number is equal to that of the light-emitting elements, each through hole is arranged between the light-emitting element and the photoconductive switch element facing each other, and drive light emitted from the light-emitting element travels to the photoconductive switch element via the through hole; and 
 wherein the second substrate has a circuit wiring connected to the photoconductive switch elements on the side facing the third substrate, and the photoconductive switch module further comprises electromagnetic shield means for the circuit wiring, the electromagnetic shield means being disposed on the third substrate on the side facing the second substrate and arranged to face the circuit wiring. 
 
   
   
     9. The photoconductive switch module according to  claim 8 , wherein the third substrate has a concave portion extending along the circuit wiring, such that the through holes terminate on the bottom surface of the concave portion, the third substrate has conductivity at least in the vicinity of the surface of the concave portion, and the conductive part in the vicinity of the surface of the concave portion constitutes the electromagnetic shield means. 
   
   
     10. A photoconductive switch module comprising:
 a first substrate having light-emitting elements; 
 a second substrate having photoconductive switch elements, whose number is equal to that of the light-emitting elements, the light-emitting elements and the photoconductive switch elements being arranged to face each other, the photoconductive switch elements being turned on/off in accordance with lighting/extinction of the light-emitting elements; and 
 a third substrate arranged between the first substrate and the second substrate, the third substrate having through holes, whose number is equal to that of the light-emitting elements, each through hole being arranged between the light-emitting element and the photoconductive switch element facing each other, drive light emitted from each light-emitting element traveling to the photoconductive switch element via the through hole; 
 wherein the second substrate has a circuit wiring connected to the photoconductive switch elements on the side facing the third substrate, the third substrate has a concave portion extending along the circuit wiring, such that the through holes terminate on the bottom surface of the concave portion, and the third substrate has conductivity at least in the vicinity of the surface of the concave portion and the third substrate further has a convex portion protruding from the bottom surface of the concave portion, and the convex portion has a height equal to or smaller than a depth of the concave portion. 
 
   
   
     11. The photoconductive switch module according to  claim 10 , wherein the convex portion is positioned between the photoconductive switch elements to be reversely turned on/off. 
   
   
     12. The photoconductive switch module according to  claim 10 , wherein the convex portion and the second substrate are spaced with a gap equal to or smaller than 100 μm, and the convex portion has a thickness (dimension in a direction along which the concave portion extends) equal to or smaller than 100 μm. 
   
   
     13. The photoconductive switch module according to  claim 10 , wherein a height of the convex portion is equal to a depth of the concave portion. 
   
   
     14. The photoconductive switch module according to  claim 10 , wherein a height of the convex portion is smaller than a depth of the concave portion. 
   
   
     15. The photoconductive switch module according to  claim 10 , wherein the convex portion surrounds the through hole.